Major changes: – Retina display compatible – Compatible with iOS 4 and support of “Fast app switching” – Pull-down to refresh and infinite scrolling in timelines – Ability to send URLs you visit to Instapaper and Read It Later

New features specific to the Twitter space: – Direct Messages are now organized by threads, and creating a new Direct Message is now much simpler with user selection – You can now create new Lists, and add people to Lists – Verified Accounts now have a “Verified” icon on their Profile – You can filter the Retweets timeline by type of Retweet -Tapping the “in reply to…” in a Tweet now display the full public conversation, not just the last reply

New features specific to the Facebook space: – The Newsfeed is now displayed much better, and will be much faster to browse – You can now read (only) your private messages inbox – Your list of Friends and Pages are now displayed and you can also see the profile of your friends and pages right from the app

It is, unfortunately, not a “Universal” app that rescales on the iPad’s display. Nor is there an iPad specific version. And, oh yes, the U.S. version of this update will features advertisements from Apple iAd.